Donald Trump has levelled his most severe threat against Canada in years, warning that on his very first day on office he might impose punishing economic sanctions across North America.

The U.S. president-elect threatened Monday evening to slap a 25 per cent import tariff on all products entering the country from Canada and Mexico on Jan. 20, 2025, his inauguration day.

He used his Truth Social media account to deliver the warning, which began with a complaint about migration and drugs spilling across both the northern and southern border into the U.S. Then he foreshadowed a damaging import fee that would drive up costs for Canadian and Mexican exporters, making their products less attractive while also potentially raising costs for American consumers.

"On January 20th, as one of my many first Executive Orders, I will sign all necessary documents to charge Mexico and Canada a 25% Tariff on ALL products coming into the United States, and its ridiculous Open Borders," Trump posted, after complaining about a caravan of migrants approaching through Mexico.

"This Tariff will remain in effect until such time as Drugs, in particular Fentanyl, and all Illegal Aliens stop this Invasion of our Country!

"Both Mexico and Canada have the absolute right and power to easily solve this long simmering problem. We hereby demand that they use this power, and until such time that they do, it is time for them to pay a very big price!"

Trump has levelled similar threats before

It's unclear whether Trump intends to proceed with the idea as described, or whether it's a negotiating ploy to extract certain actions.

Trump has levelled these sorts of threats before, usually in the context of a negotiation.

He was on the verge of officially declaring his intention to cancel the original North American Free Trade Agreement in 2017, just before negotiations began on the updated deal. As those talks hit late snags, he threatened to impose punishing tariffs on Canadian automobile exports in 2018, then lifted that threat a few days later, when Canada and the U.S. agreed to an updated trade pact.

He did actually impose tariffs on Canada in his first term, on steel and aluminum, before the countries could negotiate an exemption.

What's unclear as how this tariff threat squares with one of Trump's major promises of the campaign: to lower the cost of living in general for Americans, and the cost of gas in particular.

Oil is Canada's No. 1 export to the United States. A 25 per cent levy on oil would mount a challenge to that seminal election promise.